COVER STORY M K Gupta - Ipt.co.in

INDIAN PLUMBING TODAYCOVER STORYRevitalizationof theWater Channels& Fountainsfor the Gardens ofHumayun’sTombMahender Kumar GuptaHistory of Humayun’s TombEmperor Humayun sat on the throne at theage of 22 succeeding his father Babur, thefounder of the Mughal Empire in India.However, Humayun met an untimely deathafter a tragic fall from the steps of his libraryin the Purana Kila complex in Delhi. He was48 then. After nine years of his death, histomb was built under the supervision ofHamida Begum, his widow, during the reignof their son Akbar. The site for the tombwas chosen on the banks of Yamuna riverbecause it was Humayun’s wish to bury himnear his spiritual Guru Hazrat Nizammudin.The construction of tomb was completed in1572 A.D. at a cost of 15 lakh rupees (1.5million) at the time. It was designed by thearchitect Mirak Mirza Ghiyas, a Persianfrom Herat, now in Afghanistan. Influencedby Persian architecture, the tomb standson a platform of 120 sq. m. and reaches aheight of 47 m. Built of rubble masonry,the structure is the finest example of theuse of both red sandstone and white marbleon a large scale.NOVEMBER 2011 16

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INDIAN PLUMBING TODAYToday, the tomb of the second Mughal Emperor isamongst the twenty three World Heritage Sites in India.The chahar-bagh, or four-part paradise garden, is theearliest existing example of the Mughal garden tomb.The tomb and gardens are considered one of theprecursor typologies of the Taj Mahal.The gardens are laid out in a classical chahar-baghdesign symbolically patterned to represent the Islamicnotions of a paradise. Gardens are divided into quartersby raised causeways. The quadrants are divided, in turn,into eight plots, each with walkways. At theintersection of these walkways are octagonal orrectangular pools.COVER STORYlevels, etc. as well as different aspects of the site relatingto revitalization of the gardens through the waterchannel system. Various discussions and interactionswith the site and the other specialists involved,highlighted these requirements as well as constraintsto be kept in mind to facilitate any kind of proposal.Two major scopes were defined as integral to therevitalization of this site:(a) Revival of water channel network system(b) Revival of water fountainsRevival of Water Channel Network SystemTo be able to consider a scheme to revive water channelnetwork system of this complex, which is almost 450years old, was a daunting task, as it involved variouslayers of historical studies and assumptions, whichincluded a study of the existing conditions with notvery significant background of the original work. It alsoconsidered the fact that many changes and alterationsmay have been made to the original scheme in thesubsequent years. Some techniques/methods, whichwere followed to understand these changes, were:The main monument of Humayun’s tomb is surroundedby a network of channels, which has water flowingthrough them to create an oasis of tranquility. Thoughit is not certain, whether water used to flow throughthe system or re-circulate, the proximity of the Yamunariver in the past, and the presence of historical wellsand remains of aqueduct-like structures indicate thatwater used to flow through the system entirely bynatural means, through fountains and channels.Objective of the ProjectGardens & FountainRestoration of Humayun’s tomb was started by the AgaKhan Trust for Culture (AKTC), Geneva in collaborationwith Archaeological Survey of India (ASI) in 2000. Underthe project, major restoration and environmentaldevelopment works were taken up for this landmarksite.The objective of the project was to revitalize the gardens,pathways, fountains and water channels of the chaharbagh,or four-part paradise garden surroundingHumayun’s tomb in New Delhi. To ensure that the sitewas rehabilitated according to the original plans of thebuilders, site works encompassed a variety ofdisciplines, including archaeology, conservation scienceand hydraulic engineering.M/s MKG Consultants became associated with the AgaKhan Trust with a view to understand the hydraulicsof the existing system of water channels, its condition,• Sizing/leveling of channels and flow determination• Preparing detailed proposal of channel network• Collation of data regarding source development/treatment/pumping• Systemic understandings of distribution/collection/re-useExisting Water Channel Network• The main monument of Humayun’s tomb issurrounded by a network of channels, which passthrough the gardens, forming three rings around thetomb, namely inner, central and outer rings.Historically, water used to flow through thesechannels, presumably at relatively slow speed. Theapproximate average dimensions of channels werefound to be of a width of approximately 20-25 cmand a depth which varied from 5-30 cm.• At the time of the initial study, entire network ofwater channels was defunct. Many portions of thechannels were filled up with accumulated silt/debris.• Based on the site survey reports, the top and bottomlevels of the channels were studied thoroughly. Manylevels were irregular, presumably due to settling/filling up, as well as previous alterations, whichcould have occurred during the past centuries. Dueto this, the slopes were also irregular at mostlocations and followed an almost illogical pattern.Approach for Planning• Historically water flowed in from the centre of thenorthern side and a few meters south from thewestern side. After a detailed study of drawings andthe site regarding the levels, slopes and relatedNOVEMBER 2011 18

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INDIAN PLUMBING TODAYaspects, it was decided to propose in principle toretain this direction of flow, as maximum as possible,to ensure that minimum disturbance/nuisance iscreated within the landscaped area of the site.Considering that this project was a part of a WorldHeritage Monument and the significantarchaeological elements and historical value of thesite, it was neither desirable nor recommended toundertake any major digging work in the site area,which could have otherwise involved changes in thelevels.• The existing top stones of the channels were not tobe changed.• According to the brief obtained and as specified inthe instructions given by the ConservationArchitects, maximum efforts were made to designthe system such that the existing invert levels ofthe channels would require minimum alteration.However, to enable water to flow freely by gravity byproviding proper slope, the invert levels i.e. bottomof the channels required an alteration of 2-3 cm.• No new catch-basins, chambers, manholes or pipeswere desirable in the main areas, including thelawns. Therefore, all the proposed drainageappurtenances were proposed in the sunken area,where they would remain out of sight. Since aminimum amount of disturbance in the garden withrespect to pipes, manholes etc. was desired, no drainpipe was to be installed except in the sunken area.In fact, it was decided that the proposed system wouldattempt to eliminate the necessity for any manholes,catch basins etc. to be located within the gardens/landscaped portions of the site. Since the flow ofwater was being proposed to take place in the generaldirection from west to east by gravity, no drainpipeswere envisaged in the landscaped area in the finalsystem.• For water to continuously flow at a ‘slow’ speed,the proposed velocity of water flowing in the channelswas to range from .05 m/s to 0.5 m/s. For thispurpose, the slopes and levels were proposedaccordingly. Certain sections of the channel hadflows varying from 0.02 m/s to 0.15 m/s, due to theslopes constraint. However, this was not likely tohave a large impact on the visual appeal of theflowing water.• Since there were major variations in the existingslopes and levels, and also since the water was toapparently drain out and get wasted in some parts,the channels at certain sections were extremelydifficult to revive. Therefore, in congruence with theConservation Architects, it was proposed to revivewater flow in certain sections of the entire channelsystem.• The inlet pipe had to be a pressurized pipe and wastaken along the external boundary, however it wasrecommended to either take the inlet flow along theCOVER STORYinternal periphery, or even along the top of theboundary walls, as they were of sufficient width andsuitable for this purpose. The ConservationArchitects had also suggested the possibility of takingthe inlet pipes along the inner boundary wall beneaththe pathway. But it was found that the inlet pipeflow along the periphery was preferable. The proposedinlet points had to be along the northern andwestern sides. This also conformed to the historicalaspect, as it is believed this was the natural flowingpattern of water.• Water must re-circulate or else it becomes stagnantand a source of malady rather than joy. It wasproposed to allow water to flow from the inlet to theoutlet by means of gravity. From the outlet point,water was re-circulated and diverted back to the inletpoint. This was done using the necessary pumpingequipment. Treatment systems, grit-traps etc. wereproposed based on the water quality and probablesediment/debris accumulation.• Existing grooves and slots in the channels wereutilized for blocking the water from draining outduring periods when recirculation does not take placeto minimize water losses.Existing Grooves/Slots in the Channel• Electricity consumption was to be kept at theminimum by utilizing suitable mechanicalequipment.• It was not viable to revive the whole system withflowing water, however, it was desired that the majorportion of the inner and middle rings be madeoperational. Attempts were made to revive amaximum portion of the network, in aneconomically viable way – both for initial set up andlong-term maintenance. At the main entrance, itwas proposed to revive even the outer channel, asthis area was likely to experience the largest amountof visual attention from visitors to the monument.Also, the inlet points had to be located on thisportion of the network.• In the north-eastern segments of the channelsystem, where underlying terracotta pipes ofNOVEMBER 2011 20

INDIAN PLUMBING TODAYhistorical significance was present, no proposedchanges were made in the levels, i.e. the existinglevels were to be utilized.Renovation of FountainsIn consonance with the channels, the inlet points weredefined by chaddars, or small waterfalls. Nodes betweenthe channels would be highlighted by octagonal orrectangular shallow ponds, which would also havevarious kinds of fountains to highlight and enhancewater in various ways. It was decided to install smallgurgling fountains in the four central tanks to give anappearance, as envisaged in the original feature.COVER STORY• Probably, these fountains were operated with thehelp of low-head aqua duct. Therefore, it was decidedthat the appearance of the fountains should looknatural and no mechanical equipments should bevisible. Therefore, a small covered sump in one cornerof the tank was located and submersible pumps wereused to re-circulate water through the fountainheads, which were made up of stone having carvingmatching with the original form.• These fountains were foreseen to become veryappealing features having the main structure of thetomb in the background from all four sides – andsplashing water filled the atmosphere with coolnessin the hot northern Indian climate.Some other important factors that were simultaneouslyconsidered while working on the project proposal were:• Sufficient water should be available for the waterchannels, and the losses/wastage of water shouldbe kept to a minimum so that in the long run theburden of running the channels would be minimizedand it would also help to ensure that the channelscould become a regular feature of the site and notmerely something kept reserved for special occasions.• Rainwater should be utilized for the purpose ofrecharging the underground aquifer. The systemswere already in place and only a sensitized systemwas to be considered to revive functioning.Considering well all the main points, suggestions, andhistory, the work was executed by the specializeddraftsmen and experienced technicians. The entiresystem of channels and fountains was commissionedand inaugurated by His Highness Aga Khan along withthe Prime Minister of India on 15 th April 2003.ChaddarA Revisit of OperationsAn audit was conducted at the site on 30 th April 2011,with a view to assess the situation of the effects of theoperation and maintenance of the channels andfountains after functioning for about 8 years. It is amatter of great satisfaction that after 8 years, the entiresystem of channels and fountains is functioning wellin a very satisfactory way and is being maintained asper the original planning. The hallmark of the successof the system was perceived to be its low maintenancerequirements and its high degree of self sufficiency.Four main tanks on the channel network inwhich fountains are to be installed.The process of systemic design is itself a complex oneand when it is further obscured by trying to read through450 years of history, it becomes even more convoluted.For the very term of revitalization of something ascomplicated as a historic garden, is almost a misnomer– as technologies, working methods and groundconditions change, and all these need to be consideredand evaluated before any decision and proposal isimplemented. To work in a heavily loaded conservationsite, one finds that it is usually advisable to go back tothe ground conditions and stick to the basics - as theyNOVEMBER 2011 21

INDIAN PLUMBING TODAYCOVER STORYSome Comparison Photographs (2000 – 2011)C1 - 2000 C1 - 2003C1 - 2011C2 - 2000 C2 - 2003 C2 - 2011C3 - 2000C3 - 2003 C3 - 2011C4 - 2000C4 - 2003C4 - 2011enable a cleaner understanding of the ground realityand help facilitate the work. And in turn, it is perhapsthis philosophy which allowed this garden of paradiseanother new lease at life. IPTAcknowledgements- Mr. Ratish Nanda, Director of Aga Khan Trust for Culture in India,provided his valued assistance and guidance during the course ofthe project.- Archaeological Survey of India was Coordinator of the project.Mr. Mahender Kumar Gupta isChairman – IPA New Delhi Chapter. Heis Managing Director of M/s MKGConsultants and has more than 39 yearsof experience in the field of public healthengineering, sanitary engineering and industrial & firefightingservices. He was associated with Aga Khan Trust for Culturefor providing hydraulic services for the renovation of channelsand fountains of Humayun’s tomb. He can be contacted atnewdelhi@indianplumbing.orgNOVEMBER 2011 22